An eight year old Brooklyn boy found a winning weapon in his battle against bone cancer this week: a metal rod and a magnet. On Tuesday, doctors at The Mount Sinai Hospital gave Avrum Rosenberg a state-of-the-art solution. They removed the tumor and replaced the destroyed bone with a recently FDA-approved rod that grows when it is placed under a magnet. The magnet triggers the metal rod in his leg to expand, in an outpatient procedure that takes about 20 minutes, according to James Wittig, chief of orthopedic oncology at the hospital. "The biggest advantage is you don't have to bring the child back to the O.R., where they can risk infection, pain and trauma," said Dr. Wittig. Learn more.